New Delhi, Dec 24 (IANS): A day after the Ludhiana court blast, IANS has accessed a letter written by the Director General of Police, Internal Security, Punjab, to the police and security agencies regarding a possible strike by Lashkar-e-Toiba terrorists.

"The letter had indicated the possible target of the terrorists could be Defence, Central Armed Police Force, police establishments and courts," sources said.

This alert was sent on November 30 by the DIG internal security to the agencies and police department.

"According to a fresh input shared by a central agency, ISI has tasked Lashkar-e-Toiba to infiltrate five terrorists under the garb of Sikh individuals through Kartarpur Corridor into India after two weeks of commando training in Shakargarh (Pakistan) with directions to move to either Pathankot or Gurdaspur for further tasking," read the input.

The letter has revealed the identity of two ultras as Mohd Gulzar Maghre and Mohd Sahjada Bande.

The letter had mentioned the planning of a grenade attack against the security forces camp in Jammu and Kashmir by an Islamic terrorist outfit, Muslim Janbaaz Force.

A highly placed source said quoting the letter that the police was advised to immediately take robust round-the-clock counter measures and suitable preventive and precautionary steps.

"The agencies are asked to review the second line of defence along the India-Pakistan border in coordination with BSF, and constantly monitor the routes, gaps on the international border that have come to office, I.G.P. Ludadana Ranaticer having been used in earlier possible infiltrations by Pakistan-based terrorists," the letter said.

The DIG Internal Security had suggested in the letter to ensure deployment of Special 24x7 armed 'nakas' on all roads, routes leading to the border area to cover any ingress from vulnerable and riverine gaps on the International Border.

One person was killed and several others were reportedly injured in the blast. The NIA and other agencies are probing the incident.